Soon after 9am on September 11, 2001, I landed, on board a United Airlines flight from Hong Kong, at Chicago's O'Hare airport, intending to transfer to a flight to Washington. I never made it. Instead, I spent four days around O'Hare, before finding a train to New York and the smell of the downtown devastation. That provided a vantage point for observing the public's generally sober and unhysterical initial response to the shock.

Five years on, and the shock is of a different kind. As I write, the headline in today's International Herald Tribune reads: 'Bush plays terror card in looking to elections.' The cynicism of this underachiever, thrust into prominence by a political machine capitalising on the Bush name, is a reminder that he is probably still in office only because of repeated playing of the 'terror card'.

Even back then, one was aware of the danger of 9/11 being abused for political purposes. I wrote in the South China Morning Post at the time: 'The more we overreact, the more likely that the terrorists will achieve their ends ... it will set off a chain of further reactions that will have negative effects, particularly for America and all that is best about it. What better way to undermine the US than to incite it to the point where the US sets itself against its own principles?'

In short, the success of Osama bin Laden would be determined not by his actions, but by our reactions.

I would like to think that was merely stating the obvious. But, looking back, one can see how susceptible all societies are to fear or, more specifically, to the use of real or imagined threats for ends other than safety. It was Nazi propagandist Joseph Goebbels who noted how readily people would surrender their liberties if persuaded that their security was at risk.

So what is the balance sheet now, of the reactions of the United States, and its friends and allies, to 9/11?

On the plus side, one can say that al-Qaeda no longer exists as a small but expert and highly centralised group. In that form, it required a sanctuary such as it had in Afghanistan. The war on the Taleban was justified, not because it represented an oppressive ideology, but because it had harboured bin Laden.

On the plus side, too, one can say that greater vigilance over security has probably been effective in preventing or deterring similar kinds of spectacular attacks. However, there is a real danger here of after-the-fact justification for oppressive and invasive anti-terror legislation. Some claims that attack plans have been foiled have proved to be exaggerated - if not invented for propaganda purposes.

The other question is whether the post-9/11 events have generated more terror attacks than have been foiled by increased measures. That is unanswerable. But the London bombings by locally born Muslims, and the Madrid bombs, could be seen as reactions to post-9/11 events - the Iraq invasion and perceptions that Muslims have been demonised.

What one can say without doubt is that there was never a shred of evidence of al-Qaeda links to justify the Iraq invasion. Other justifications might have existed, but the reality is that the 'war on terror' was used to justify an invasion that was the product of a coalition of diverse interests in Washington. Those start with US President George W. Bush's desire to prove his manhood. Their ranks include traditional warriors Defence Secretary Donald Rumsfeld and Vice-President Dick Cheney, and Christian fundamentalists - in an alliance of convenience with a pro-Israel lobby happy to see any chaos in the Arab world.

The Iraqi invasion has had many results. For one, the reconstruction of Afghanistan has been so neglected that chaos and opium growing have returned with a vengeance.

The invasion has brought near civil war to Iraq. The war is mainly between Sunnis and Shi'ites, but it is complicated by the survival of Saddam Hussein's forces and the presence of bin Laden-inspired holy warriors. Democracy is meaningless, and the secular focus of the previous regime is being replaced in many areas by imposed religious values.

Further, Iraqi Kurdish autonomy is bringing peace to that region but storing up trouble for the future, particularly with Turkey. As for Hussein, his trial is a reminder of the west's past complicity in his wars against the Kurds and Iran.

The cost of Iraq to the United States is mounting. The guns-and-butter policies of Mr Bush exceed even those of former US president Lyndon Johnson, who tried to create the so-called 'Great Society' while running a costly war in Vietnam. Given an ageing population, today's war debts are more serious for the US than those of previous wars.

The atmosphere in the Middle East has been rendered more poisonous than ever by the mess in Iraq, the unqualified US backing for Israeli expansionism, the use of political assassination and 'collateral' killing of civilians. The most obvious consequence has been the rise of the influence of Iran, headed by a dangerous populist president, Mahmoud Ahmadinejad, rather than the moderate and sophisticated former president, Mohammad Khatami. The Iraq war and the US alliance with a nuclear Israel have spurred Iran's own nuclear ambitions.

Guantanamo and the secret CIA prisons will remain a blot on the US for decades to come. It will probably leave a greater, more lasting sense of guilt than the second-world-war incarceration of citizens of Japanese descent.

Elsewhere, notably in Britain and Australia, copycat 'anti-terror' legislation has undermined ancient liberties and increased the power of the executive. Rather than helping combat terrorism, it has alienated Muslim minorities. The integration of these minorities was already a problem in Britain and France, in particular, and has now been exacerbated. It has not yet surfaced as a problem in the US, but could do so.

The response to 9/11 has resulted in increasing confusion over three issues. First, the Palestine and Israel matter is really a struggle over land, but religion has filled the gap left by the failures of secular, west-aligned Arabs. Second is the internal Islamic struggle between fundamentalism and modern pluralism, with post-9/11 events strengthening the influence of the former.

Third, the integration of Muslims in western societies was a difficult enough task even without the political exploitation of the 'terror threat'.

In short, the west should weep for its values, as well as for the lives that were lost five years ago.